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  <title>Document</title>
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      <option value="java">Java从入门到精通</option>
      <option value="python">python从入门到精通</option>
      <option value="php">php从入门到精通</option>
      <option value="mysql">mysql从删库到跑路</option>
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    data: {
      mySelect: 'php'
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